Cookbook > Building Subgraphs on Arweave

Building Subgraphs on Arweave

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Arweave support in Graph Node and on Subgraph Studio is in beta: please reach us on Discord with any questions about building Arweave subgraphs!

In this guide, you will learn how to build and deploy Subgraphs to index the Arweave blockchain.

What is Arweave?

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The Arweave protocol allows developers to store data permanently and that is the main difference between Arweave and IPFS, where IPFS lacks the feature; permanence, and files stored on Arweave can't be changed or deleted.

Arweave already has built numerous libraries for integrating the protocol in a number of different programming languages. For more information you can check:

  • Arwiki
  • Arweave Resources

What are Arweave Subgraphs?

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The Graph allows you to build custom open APIs called "Subgraphs". Subgraphs are used to tell indexers (server operators) which data to index on a blockchain and save on their servers in order for you to be able to query it at any time using GraphQL.

Graph Node is now able to index data on Arweave protocol. The current integration is only indexing Arweave as a blockchain (blocks and transactions), it is not indexing the stored files yet.

Building an Arweave Subgraph

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To be able to build and deploy Arweave Subgraphs, you need two packages:

  1. @graphprotocol/graph-cli above version 0.30.2 - This is a command-line tool for building and deploying subgraphs. Click here to download using npm.
  2. @graphprotocol/graph-ts above version 0.27.0 - This is library of subgraph-specific types. Click here to download using npm.

Subgraph's components

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There are three components of a subgraph:

1. Manifest - subgraph.yaml

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Defines the data sources of interest, and how they should be processed. Arweave is a new kind of data source.

2. Schema - schema.graphql

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Here you define which data you want to be able to query after indexing your Subgraph using GraphQL. This is actually similar to a model for an API, where the model defines the structure of a request body.

The requirements for Arweave subgraphs are covered by the existing documentation.

3. AssemblyScript Mappings - mapping.ts

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This is the logic that determines how data should be retrieved and stored when someone interacts with the data sources you are listening to. The data gets translated and is stored based off the schema you have listed.

During subgraph development there are two key commands:

$ graph codegen # generates types from the schema file identified in the manifest
$ graph build # generates Web Assembly from the AssemblyScript files, and prepares all the subgraph files in a /build folder

Subgraph Manifest Definition

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The subgraph manifest subgraph.yaml identifies the data sources for the subgraph, the triggers of interest, and the functions that should be run in response to those triggers. See below for an example subgraph manifest for an Arweave subgraph:

specVersion: 0.0.5
description: Arweave Blocks Indexing
schema:
file: ./schema.graphql # link to the schema file
dataSources:
- kind: arweave
name: arweave-blocks
network: arweave-mainnet # The Graph only supports Arweave Mainnet
source:
owner: 'ID-OF-AN-OWNER' # The public key of an Arweave wallet
startBlock: 0 # set this to 0 to start indexing from chain genesis
mapping:
apiVersion: 0.0.5
language: wasm/assemblyscript
file: ./src/blocks.ts # link to the file with the Assemblyscript mappings
entities:
- Block
- Transaction
blockHandlers:
- handler: handleBlock # the function name in the mapping file
transactionHandlers:
- handler: handleTx # the function name in the mapping file
  • Arweave subgraphs introduce a new kind of data source (arweave)
  • The network should correspond to a network on the hosting Graph Node. In Subgraph Studio, Arweave's mainnet is arweave-mainnet
  • Arweave data sources introduce an optional source.owner field, which is the public key of an Arweave wallet

Arweave data sources support two types of handlers:

  • blockHandlers - Run on every new Arweave block. No source.owner is required.
  • transactionHandlers - Run on every transaction where the data source's source.owner is the owner. Currently an owner is required for transactionHandlers, if users want to process all transactions they should provide "" as the source.owner

The source.owner can be the owner's address, or their Public Key.

Transactions are the building blocks of the Arweave permaweb and they are objects created by end-users.

Note: Irys (previously Bundlr) transactions are not supported yet.

Schema Definition

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Schema definition describes the structure of the resulting subgraph database and the relationships between entities. This is agnostic of the original data source. There are more details on the subgraph schema definition here.

AssemblyScript Mappings

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The handlers for processing events are written in AssemblyScript.

Arweave indexing introduces Arweave-specific data types to the AssemblyScript API.

class Block {
timestamp: u64
lastRetarget: u64
height: u64
indepHash: Bytes
nonce: Bytes
previousBlock: Bytes
diff: Bytes
hash: Bytes
txRoot: Bytes
txs: Bytes[]
walletList: Bytes
rewardAddr: Bytes
tags: Tag[]
rewardPool: Bytes
weaveSize: Bytes
blockSize: Bytes
cumulativeDiff: Bytes
hashListMerkle: Bytes
poa: ProofOfAccess
}
class Transaction {
format: u32
id: Bytes
lastTx: Bytes
owner: Bytes
tags: Tag[]
target: Bytes
quantity: Bytes
data: Bytes
dataSize: Bytes
dataRoot: Bytes
signature: Bytes
reward: Bytes
}

Block handlers receive a Block, while transactions receive a Transaction.

Writing the mappings of an Arweave Subgraph is very similar to writing the mappings of an Ethereum Subgraph. For more information, click here.

Deploying an Arweave Subgraph in Subgraph Studio

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Once your subgraph has been created on your Subgraph Studio dashboard, you can deploy by using the graph deploy CLI command.

graph deploy --studio --access-token <your-access-token>

Querying an Arweave Subgraph

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The GraphQL endpoint for Arweave subgraphs is determined by the schema definition, with the existing API interface. Please visit the GraphQL API documentation for more information.

Example Subgraphs

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Here is an example subgraph for reference:

Can a subgraph index Arweave and other chains?

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No, a subgraph can only support data sources from one chain/network.

Can I index the stored files on Arweave?

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Currently, The Graph is only indexing Arweave as a blockchain (its blocks and transactions).

Can I identify Bundlr bundles in my subgraph?

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This is not currently supported.

How can I filter transactions to a specific account?

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The source.owner can be the user's public key or account address.

What is the current encryption format?

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Data is generally passed into the mappings as Bytes, which if stored directly is returned in the subgraph in a hex format (ex. block and transaction hashes). You may want to convert to a base64 or base64 URL-safe format in your mappings, in order to match what is displayed in block explorers like Arweave Explorer.

The following bytesToBase64(bytes: Uint8Array, urlSafe: boolean): string helper function can be used, and will be added to graph-ts:

const base64Alphabet = [
"A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M",
"N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z",
"a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m",
"n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z",
"0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "+", "/"
];
const base64UrlAlphabet = [
"A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M",
"N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z",
"a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m",
"n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z",
"0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "-", "_"
];
function bytesToBase64(bytes: Uint8Array, urlSafe: boolean): string {
let alphabet = urlSafe? base64UrlAlphabet : base64Alphabet;
let result = '', i: i32, l = bytes.length;
for (i = 2; i < l; i += 3) {
result += alphabet[bytes[i - 2] >> 2];
result += alphabet[((bytes[i - 2] & 0x03) << 4) | (bytes[i - 1] >> 4)];
result += alphabet[((bytes[i - 1] & 0x0F) << 2) | (bytes[i] >> 6)];
result += alphabet[bytes[i] & 0x3F];
}
if (i === l + 1) { // 1 octet yet to write
result += alphabet[bytes[i - 2] >> 2];
result += alphabet[(bytes[i - 2] & 0x03) << 4];
if (!urlSafe) {
result += "==";
}
}
if (!urlSafe && i === l) { // 2 octets yet to write
result += alphabet[bytes[i - 2] >> 2];
result += alphabet[((bytes[i - 2] & 0x03) << 4) | (bytes[i - 1] >> 4)];
result += alphabet[(bytes[i - 1] & 0x0F) << 2];
if (!urlSafe) {
result += "=";
}
}
return result;
}
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